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Inequality (!=)

The != operator checks whether its two operands are not equal, returning a Boolean result. Unlike the strict inequality operator, it attempts to convert and compare operands that are of different types.

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Syntax

x != y

Description

The inequality operator checks whether its operands are not equal. It is the negation of the equality operator so the following two lines will always give the same result:

x != y;

!(x == y);

For details of the comparison algorithm, see the page for the equality operator.

Like the equality operator, the inequality operator will attempt to convert and compare operands of different types:

3 != "3"; // false

To prevent this, and require that different types are considered to be different, use the strict inequality operator instead:

3 !== "3"; // true

Examples

Comparison with no type conversion

1 != 2; // true
"hello" != "hola"; // true

1 != 1; // false
"hello" != "hello"; // false

Comparison with type conversion

"1" != 1; // false
1 != "1"; // false
0 != false; // false
0 != null; // true
0 != undefined; // true
0 != !!null; // false, look at Logical NOT operator
0 != !!undefined; // false, look at Logical NOT operator
null != undefined; // false

const number1 = new Number(3);
const number2 = new Number(3);
number1 != 3; // false
number1 != number2; // true

Comparison of objects

const object1 = {
  key: "value",
};

const object2 = {
  key: "value",
};

console.log(object1 != object2); // true
console.log(object1 != object1); // false

Specifications

Specification
ECMAScript Language Specification # sec-equality-operators

Browser compatibility

	Desktop						Mobile						Server
	Chrome	Edge	Firefox	Opera	Safari	Chrome Android	Firefox for Android	Opera Android	Safari on IOS	Samsung Internet	WebView Android	Deno	Node.js
`Inequality`	1	12	1	3	1	18	4	10.1	1	1.0	4.4	1.0	0.10.0